In /usr/bin/hsc2hs line 5:
datadir="/usr/share"
^-----^ SC2034: datadir appears unused. Verify use (or export if used externally).


In /usr/bin/hsc2hs line 6:
bindir="/usr/bin"
^----^ SC2034: bindir appears unused. Verify use (or export if used externally).


In /usr/bin/hsc2hs line 37:
exec "$executablename" ${tflag:+"$tflag"} $HSC2HS_EXTRA ${1+"$@"} "$Iflag"
                                          ^-----------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
exec "$executablename" ${tflag:+"$tflag"} "$HSC2HS_EXTRA" ${1+"$@"} "$Iflag"

For more information:
  https://www.shellcheck.net/wiki/SC2034 -- bindir appears unused. Verify use...
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...